(!!) (Best Value Single) ECC83=12AX7 Tungsram Hungary 1980 era branded Amperex NOS 1985 (1.3/1.6ma and Gm=1800/1800)

1 low noise tube) ECC83=12AX7 Tungsram Hungary 1980 era branded Amperex NOS 1985

1 section) Gm=1800 (1.3ma)

1 section) Gm=1800 (1.6ma)

Good Gm range 1600-1800

Good mA range = 1.0mA+